1. Field of Invention
This invention relates generally to flexible packages and more particularly to flexible packages including a fitment for dispensing a metered amount of liquid within the packages.
2. Description of Related Art
Numerous patents disclose flexible packing for holding liquids and for dispensing the liquid through a fitment outlet or tap forming a portion of the package. For example, U.S. Pat. No. 4,429,810 (Hample et al.), U.S. Pat. No. 3,696,969 (De Van et al.), U.S. Pat. No. 4,314,654 (Gaubert), U.S. Pat. No. 4,416,395 (Gaubert), U.S. Pat. No. 4,452,378 (Christine), U.S. Pat. No. 4,602,725 (Malpas et al.), U.S. Pat. No. 6,131,767 (Savage et al.), U.S. Pat. No. 6,446,845 (Steiger) and published application 2005/0121464A1.
The devices of the above identified prior art make use of gravity to enable the liquid within the flexible package to be dispensed from the package. As will be appreciated by those skilled in the art, when the contents of the flexible package has reached a very low level there may not be sufficient static head to enable the dispensing of further amounts, thereby leaving some liquid still within the package. Moreover, the dispensing packages of the prior art making use of gravity as the mechanism for effecting the dispensing operation may not provide precise and repeatable metering of the liquid being dispensed.
Flexible packages for use with pumps also exist in the prior art. See for example, U.S. Pat. Nos. 4,576,313 (Smith et al.), U.S. Pat. No. 5,819,986 (Last et al.) and U.S. Pat. No. 6,082,584 (Stern).
While the aforementioned packages with fitments may be generally suitable for their intended purposes, they suffer from one or more of the drawbacks, e.g., simplicity of construction, low cost, effectiveness in dispensing repeated metered amounts of liquid, and effectiveness dispensing the entire contents of the package. The subject invention addresses the needs of the prior art.